Antrodia camphorata is perennial basidiomycetes belonging to family Polyporales of order Aphyllophorales in class Basidiomycetes, grows only in Cinnamomum kanehirae in Taiwan, and is a rare edible and medicinal fungus. Its mycelium and fruiting bodies have many physiological activities, such as liver protection, anti-oxidation and anti-inflammation. Polysaccharides, terpenoids and steroids are the main active compounds of Antrodia camphorata. Triterpenoids are one of the most important active substances. They are natural compounds composed of isoprene as a constitutional unit, which are connected end to end after removal of the hydroxyl group. Pharmacological studies have shown that the triterpenoids of Antrodia camphorata have multiple biological activities, such as liver protection, immunoregulation, anti-inflammation, anti-oxidation, blood pressure lowering, etc., and have a good therapeutic effect on tumors and cancers. Antrodia camphorata existing in nature grows on Cinnamomum kanehirae, grows very slowly, is sparsely populated, and is expensive.
Traditional edible and medicinal fungi are often cultured in a solid cultivation mode, and their growth environment conditions are close to the natural state, but the solid cultivation has the defects of long culture period and unstable metabolite bioactivities and is prone to microbiological contamination. Compared with traditional solid cultivation, the characteristics of short period and easy scale-up of liquid fermentation are more prominent. Many fungi that are not easily succeeded by artificial solid cultivation, such as Antrodia camphorata and Collybia maculata, have also successfully achieved liquid fermentation. However, since the triterpenoids of Antrodia camphorata are mainly present in the mycelium (i.e., inside the cell), the determination of the triterpenoids of Antrodia camphorata in the fermentation process needs the steps of (1) sampling, (2) solid-liquid separation, (3) room-temperature leaching, decoction or heat reflux extraction on mycelium by using organic solvents and (4) assay determination of extracted samples, and takes a long time, and especially in the third step, it takes 3 hours or more, with obvious delay. Whether in experimental research or industrial production, this delay is very unfavorable for real-time monitoring and control of the Antrodia camphorata liquid fermentation process with triterpenoids as the target product. Therefore, it is urgent and necessary to establish a method for rapidly characterizing the variation trend of content of triterpenoids in the liquid fermentation process of Antrodia camphorata. 